On the following three nights, Tom and Huck keep watch for Injun Joe outside the tavern, but he does not appear. On the fourth night, Tom enters the alley next to the tavern and disappears. When he reappears, he shouts at Huck to run for his life. When they reach the safety of the deserted slaughter-house, Tom tells Huck what he saw. He had tried the door of the tavern room and found it open. He had seen Injun Joe lying asleep on the floor, apparently drunk. The room also contains bottles and barrels of whiskey. The tavern is a Temperance Tavern, which means it is not supposed to serve alcohol. Tom realizes that the reason the room is kept locked is not because it is haunted but because it is used as a secret alcohol store. Tom says he did not see the box of treasure or the cross that Injun Joe had told his companion about at the haunted house.
Huck suggests that as Injun Joe is drunk, this would be a good time to go back and get the box. Tom disagrees, as there was only one empty bottle next to Joe and he is probably not drunk enough for their safety. They agree that Huck will watch every night until Joe leaves the room. Then, Huck will fetch Tom, who will go in and look for the box of treasure.
Tom hears that Becky is back from vacation, and joins her to play games. Becky's mother has agreed to the picnic, and invitations are sent out. The children decide to go downriver on the ferry-boat to have their picnic near a cavern. Mrs Thatcher tells Becky to spend the night with one of her friends who lives near the ferry, and they agree on the Harpers' house. After the children leave, Tom persuades Becky to stay instead with the Widow Douglas, who will have ice-cream. Tom worries that Injun Joe may leave his room that night and that he will miss Huck's signal, but he dismisses the thought because he does not want to miss the fun at Widow Douglas's house.
After the picnic, the children explore the cave. It is a vast labyrinth that nobody knows their way around. The children emerge and catch the ferry back home. Meanwhile, Huck is keeping watch outside the tavern. He sees two men emerge from the room, one carrying a box. Huck sees no point in going to fetch Tom, as the men will get away with the treasure, so he follows them. They go to Cardiff Hill, where the Widow Douglas's house is situated. Huck overhears Injun Joe say that he is disappointed to see from the lights in the house that the widow has company. Huck realizes that this is the "revenge" job that Injun Joe was talking about at the haunted house. The widow has been kind to Huck, and he wants to warn her, but does not dare, in case the men catch him.
Injun Joe goes on to tell his companion, the same man who accompanied him in the haunted house, that he wants revenge on the widow because her husband was a justice of the peace who horsewhipped and jailed him for vagrancy. Joe plans to "slit her nostrils" and "notch her ears like a sow's" in order to spoil her looks. Injun Joe threatens to kill his companion if he flinches from helping him do the deed. He says they must wait until the lights are out in the house.
Huck runs to the house of an old Welshman (Mr Jones) and tells him that the widow is in danger. Mr Jones and his sons arm themselves and set off for the widow's house. Huck hides behind a boulder and waits. He hears the sound of gunshots and a cry, and runs off.
The next day, a Sunday, Huck goes to Mr Jones's house to find out what happened. He is welcomed inside. Mr Jones tells him that he had crept up on the men but could not stop himself from sneezing. On hearing the noise, the men had fled. Mr Jones and his sons had fired at them but the men had got away. A posse has been set to guard the river and the sheriff's men are going to search the woods when it gets light. Mr Jones asks Huck to give a description of the men. Huck describes one as the deaf and dumb Spaniard, without mentioning that this is Injun Joe. Though Mr Jones has seen the Spaniard and his companion around town, he is unaware of his true identity. Mr Jones sends his sons to tell the sheriff who to look for. Huck first makes them promise not to reveal that it was he who informed on the men, as he could be killed.
In response to Mr Jones's questions, Huck tells him that he was following the men, though he carefully avoids mentioning that he was tracking their treasure. He slips up when he reports the Spaniard's saying that he would spoil the Widow Douglas's looks, thus revealing that the Spaniard is not deaf and dumb. Mr Jones reassures Huck that he will protect him, and asks what he knows about the Spaniard. Huck admits that he knows he is Injun Joe.
Mr Jones tells Huck that the men dropped a bundle of burglar's tools before they escaped. Huck is much relieved, as this means that the box of treasure must still be at the tavern.
Soon, the whole town has heard about the incident at the Widow Douglas's, and climb up Cardiff Hill to see the place where it happened. There is a knock at Mr Jones's door and Huck dives for a hiding place, not wanting anyone to connect him with the incident. The visitor is the Widow Douglas, who has come to thank Mr Jones for saving her life. Mr Jones tells her that there is someone else to whom she owes greater thanks, but that he wishes to remain anonymous. He is referring to Huck.
At church, Mrs Thatcher asks Mrs Harper where Becky is. Mrs Harper says that she did not stay with her. Aunt Polly is also wondering where Tom is, but no one knows. The children returning from the picnic on the ferry-boat did not notice whether Tom and Becky were on board. One boy says he thinks they are still in the cave. The townspeople instantly forget about the Cardiff Hill incident and launch a search for the children. The search continues all night, but without success.
When Mr Jones returns home the next morning, he finds Huck still in the bed he had provided for him, delirious with fever. The Widow Douglas, unaware of Huck's part in saving her life, comes to look after him.
By early that afternoon, many of the searchers have given up. They report that parts of the cavern that have never been explored before have been searched, and all that has been found are the words "Becky" and "Tom" written on the cave wall with candle smoke, and one of Becky's ribbons.
Three days and nights pass, and there is still no sign of the children. From his sick-bed, Huck asks the Widow Douglas if anything has been found at the Temperance Tavern, and she replies that alcohol has been found and that the tavern has been closed down. Huck believes that the treasure has been lost forever.
Analysis of Chapters 29-31
On the night of the picnic, Tom knows there is a chance that Injun Joe will appear the same night and that Huck will need his help, but he dismisses the thought because he is more charmed by the thought of spending time with Becky. Tom's desertion of his duty is a symptom of his irresponsible and still immature nature. In Tom's absence, Huck finds himself thrust into the centre of events as he witnesses Injun Joe's plotting to carry out a horrific revenge mutilation of the Widow Douglas. Huck is prompted to act by the widow's past kindness to him. He alerts Mr Jones, saving the widow from Injun Joe's malice. Huck overtakes Tom as the hero in this final part of the Injun Joe narrative thread. Huck has performed an unselfish act on a par with Tom's testifying in court.
Huck is not, however, a stereotypical or romantic hero. His primary aim throughout the novel is to remain in the background and avoid trouble. When trouble comes to him, his first instinct is to flee. These anti-heroic tendencies are evident when, unlike Tom, he does not dare to move in order to escape from the haunted house when Injun Joe and his companion are there. He has to be persuaded by Tom into such initiatives as following Injun Joe; he tries his best to avoid identifying Injun Joe to Mr Jones in an attempt to save himself from Joe's revenge; and from the same motive, he hides from the Widow Douglas rather than risk people knowing that he is the one who saved her.
It is impossible to criticize Huck for these retreating tendencies when they are probably responsible for his survival so far. Huck, unlike Tom, has no adult protector and is a social outcast. Like a wild animal, his best chance is to lie low and if discovered, to run away. But because Huck does his duty and stays at his post when Tom is getting himself and his girlfriend lost in a cave, he is rewarded by becoming the reluctant hero of the Cardiff Hill incident. This is a role that Tom would surely crave, if it were a matter of taking the glory and avoiding the lethal danger of Injun Joe's revenge. But Huck is not remotely interested in glory, wanting only to stay out of sight and survive.
The discovery of alcohol in the Temperance Tavern, like the Sunday school that excels in "showing off," the church congregation that finds a beetle more interesting than the sermon, and the strict schoolteacher who gets drunk before Examination day, provides another opportunity for Twain to satirize adult pretensions to morality. Far from being haunted, as its reputation claims, the room used by Injun Joe is in fact the illicit liquor store. The implication is that if this piece of hypocrisy in the midst of the town did not exist, Injun Joe would have one less hiding place from which to pursue his criminal activities.
The Adventures of Tom Sawyer: Novel Summary: Chapter 29 - 31